In modern professional horticulture, medicinal crops such as cannabis and high-yielding vegetable production, root zone management is the cornerstone of consistent quality and yield. Rockwool substrates offer a very stable and correctable root environment, but this advantage is fully exploited when decisions are supported by reliable and well-interpreted data. Sensors in the root zone provide continuous information on water content, EC and temperature. Used correctly, they allow growers to anticipate plant needs rather than reacting to stress signals. Used incorrectly, they introduce noise, false confidence, and misdirection. The difference is in strategy, location and interpretation. Remember that sensors are just another tool and should not replace traditional monitoring methods.

Why Root Zone Monitoring Becomes Essential at Scale
Every grower evaluates the root zone, consciously or not. In smaller installations, this is often done visually and by touch: lifting blocks, assessing the color of rockwool, or observing the attitude of plants. These methods are valuable, but subjective and difficult to standardize.

As operations grow and the number of plants increases, manual assessment quickly reaches its limits. Weighing slabs or blocks on a scale adds objectivity, but at discrete moments and with significant manual labor. In larger facilities, the manpower required to continuously monitor root conditions throughout the crop is simply not available.

Root zone sensors address this reality. They provide continuous data streams that show trends, dynamics and responses to irrigation and climate change over time. In scaled cultivation, sensors are therefore not only a precision tool, but a practical necessity. Importantly, they do not replace experience; they formalize, making intuition measurable and repeatable.

© CULTIWOOL SA
Location, representation and care of sensors
A sensor does not measure the crop; measures the exact micro-environment in which it is installed. Correct positioning is therefore essential.

Sensors should be installed in the active root zone of a healthy, representative plant, at a depth where the roots remain active throughout the crop cycle. They should never be placed directly next to a drip, as this results in high moisture readings that do not reflect average root conditions. Therefore, consistent dripper placement is essential not only for block performance, but also for consistent sensor data.

The wider greenhouse context matters just as much. Sensors should not be placed in corners, edges, near walkways or in areas subject to shadows, drafts or uneven watering. Border plants and atypical sites experience conditions different from the majority of the crop and will yield data that are not representative of the compartment.

Once installed, the sensors must remain in place for the duration of the crop cycle. Repeated removal and reinsertion disturbs the structure of the rockwool, alters the local water distribution, and compromises the consistency of the data. If a sensor needs to be removed, it should never be put back in the same place. Previously used insertion points contain moisture and residual pockets that can affect EC readings. In such cases, the sensor must be installed in a new, unobstructed location.

Consistency in positioning is what allows producers to confidently recognize trends, responses and deviations.

How many sensors are enough?
A single sensor can never represent an entire greenhouse, and in most cases, not even an entire compartment. Changes in light distribution, uniformity of irrigation, air flow and plant development inevitably create them within the crop.

At the same time, the deployment of sensors must be economically rational. The goal is not maximum sensor density, but reliable representation. In practice, this means installing multiple sensors per compartment in areas with comparable growing conditions.

Instead of focusing on individual readings, the most robust approach is to work with average data. Each sensor reflects the conditions of its specific location; by combining their readings, growers create a stable reference that reduces the risk of overreaction to local changes and supports safer and more consistent decision-making. Again, a sensor is just one tool to consider.

Interpreting root zone data in rockwool
Rockwool allows precise control of the air-water ratio in the root zone. Sensors should therefore be used to observe dynamics rather than isolated values.

Meaningful interpretation is based on the behavior of the back-dry between irrigation events, wetting rate, EC stability and how these parameters respond to climatic conditions. Sudden spikes or drops often indicate improper watering, uneven distribution, or location effects rather than actual plant demand.

Root zone data gain real value when cross-referenced with climate parameters such as temperature, humidity and VPD, as well as visual observations of crops. Integrated platforms and multiple data sources, such as those enabled by solutions like SenseNL, help validate trends and clarify cause-and-effect relationships.

Selecting the right sensor for the right substrate
Not all sensors in the root zone are interchangeable. Sensor technology must be matched with the physical properties of the substrate to generate accurate and meaningful data. They must also be properly maintained and stored to ensure accuracy.

Different substrates, such as rockwool and cocopeat, have fundamentally different structures, water retention characteristics and EC dynamics. Sensors designed for cocopeat will not give reliable readings on rockwool, and vice versa.

Also in rockwool cultivation, the selection of sensors is important. Blocks and slabs differ in volume, water distribution and root development patterns. Sensors designed for stone wool blocks are therefore not always suitable for slabs, and vice versa. Matching the sensor to the substrate material and its form factor is critical to obtaining reliable root-site data.

Driving for uniformity and stability
In both medicinal and vegetable cultivation, success is defined by uniformity and repeatability. Correctly installed and correctly interpreted root zone sensors help to identify variability early, reduce differences between plants and support stable establishment or vegetation strategies.

Combined with high-quality stone wool substrates, the sensors become a powerful ally in precision farming, improving consistency without replacing the grower’s experience.

From data points to confident decisions
Root zone sensors aren’t about collecting more numbers; they are about creating clarity. When sensors are strategically placed, deployed in sufficient numbers, and handled consistently, they make rockwool farming a predictable and correctable system.

By averaging data from multiple representative locations, producers reduce risk, avoid overcorrection, and drive with confidence. In professional horticulture, where uniformity, stability and scale define success, reliable root zone data becomes the basis rather than an experiment, cycle after cycle.

For more information:
Cultiwool
(email protected)
www.cultiwool-substrate.com

Hawaii’s Senate has passed a bill that would create a psychedelic task force tasked with studying and making policy recommendations on providing access to breakthrough therapies like psilocybin and MDMA.

After moving through the committee process, the full Senate on Friday approved Sen. Chris Lee’s (D) legislation by a 24-0 vote and sent it to the House of Representatives for consideration.

The measure would create the Emerging Mental Health Therapies Task Force, which for two years will review the current scientific literature, support additional clinical research, and develop policy recommendations for the “safe, ethical, and culturally informed implementation” of a psychedelic therapy program.

“The Legislature believes in addressing the mental health crisis affecting the State’s residents, particularly among veterans, first responders and trauma survivors,” SB 3199 reads. “Suicide remains the leading cause of preventable death, and the State must explore all safe and effective treatment options supported by scientific evidence.”

Given that the Federal Food and Drug Administration (FDA) has designated psilocybin and MDMA as breakthrough therapies in the treatment of serious mental health conditions, which may be subject to future control under the Controlled Substances Act (CSA), Hawaii’s legislation states that the state must “proactively prepare public health, clinical and research systems for safe and equitable implementation.”

Team members should include representatives from the State Department of Health (DOH), the Office of the Attorney General, the Office of Wellness and Resiliency (OWR), the University of Hawaii School of Medicine, and more.

As in the draft, the task force was to be overseen by the DOH, but this was changed in the commission to be “the responsibility of an entity with proven experience in primary scientific research and pharmaceutical or medical education.”

“The administrative work of the task force within an entity with proven experience in primary scientific research and pharmaceutical or medical teaching shall not be construed to transfer, delegate, reduce, extend, or otherwise modify any regulatory, enforcement, licensing, programming, or regulatory authority vested in the Department of Health, the Board of Pharmacy, or any other billing agency. “All statutory authority relating to controlled substances, professional licensing, and public health regulations is provided by law. They will be left to the appropriate executive authorities.”

It seems invoice would be It was first assembled in 2023 based on prior work by a separate psychedelic task force.With a similar goal of exploring avenues for therapeutic access in breakthrough drugs approved by the FDA such as psilocybin.

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It’s Marijuana Time tracking hundreds of cannabis, psychedelic and drug policy bills in state legislatures and Congress this year. Patreon supporters by pledging at least $25/month, you’ll get access to our interactive maps, charts, and audio calendars so you never miss a development.

Learn more about our marijuana bill tracking and become a Patreon supporter to gain access
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Meanwhile, Hawaii senators recently passed a bill to legalize low-dose, low-potency marijuanaalthough members of the House of Representatives say that the ban on cannabis will not end this year in the state.

A separate marijuana legalization bill, SB 2421, that contained provisions under federal reform law or amendments to the state Constitution, was delayed for action. The Senate and House panels also delayed action on a measure to sell certain hemp-derived cannabinoid products.

Senate committee action follows Senior lawmakers in the House indicated that proposals to legalize cannabis would not move forward In the 2026 session, citing the lack of sufficient support in their chamber.

On Thursday, another Hawaii Senate committee separately approved legislation to allow patients immediately enter medical cannabis after submitting their recordsinstead of waiting for the cards to be delivered, as is the case under current legislation.

user photo CostaPPR.

After almost thirty years, Alfred Boot will leave Herkuplast, currently part of the Bachmann Group, and the horticulture sector. His career has paralleled a period of profound change in the industry: from manual and seasonal production to year-round automated supply chains with high demands for uniformity, hygiene and circularity. His successor, Kasper Rietvelt, is now ready to take Bachmann-Herku to the next stage.

© Arlette Sijmonsma | MMJDaily.comAlfred Boot and Kasper Rietveld

From 26 models to customized automation solutions
“I fell into it by accident,” says Boot, reflecting on 1987, when he got into horticulture after finishing trade school. “At Rover, I immediately found myself in a world where technology and practice go hand in hand.” In the mid-1990s he was asked to set up the export operation of Herkuplast, a German manufacturer of thermoformed trays that had already been operating for several years.

“We started with 26 models. All on one A4 sheet,” he recalled. At that time, most of Herkuplast’s range consisted of multi-purpose trays, while other tray manufacturers in the Dutch market had already switched to a wider range of single-use thin models. Boot saw the place to mark his career. “We had a thin-walled model, but more was required. I was given carte blanche to develop thin models. Mr. Kubern’s collaboration with the owner Herkuplast focused on exactly that: if you have a good idea, we make it happen.”

The rise of automation in the sector placed new demands on the trays. Accuracy became critical for shot plates and automated processing lines. “Centered drain holes, exact dimensions, everything had to be right. Otherwise the line would get stuck. We always prioritized that, and it got us recognition in the market.”

2013 at the OFA Short Course in Columbus, Ohio, the predecessor to Cultivate.

Internationalization and hygiene conditions
Along with the Dutch market, Boot also moved into international markets from the start, in France, Spain, the United Kingdom, the United States and beyond. The reasoning was largely practical: in the 1990s, the sector still had a clearly defined summer break. “Production was closed for three or four weeks. The demand simply dropped. But we wanted to produce all year round, so we looked for markets that demanded it: soft fruit and cuttings propagation, for example.”

The demand for trays used in strawberry, raspberry and blueberry production enabled year-round manufacturing and became a growing market segment. “Retailers and consumers expect that. That’s reflected in volumes and specifications.”

At the same time, hygiene requirements in breeding increased with increasing virus pressure and a smaller range of approved crop protection products. “Multi-use trays are easy to clean, cheaper than injection-molded alternatives, and are pocketable. And because thermoformed trays are thinner, if something goes wrong on an automated line, you lose the tray, not the robot arm,” explains Boot.

That said, the priority has always been to maximize the use of plastic through reuse. This has also changed significantly over the decades. “When I started, plastic was treated as waste. It was thrown away or burned. That is completely out of the question today.” Herkuplast, working with partners like Van Krimpen, has invested heavily in circular solutions. “Our breeding and growing trays do not enter the consumer market. They go from the dealer to the packaging operation. In the Netherlands, the used trays are collected, shredded and reprocessed as raw material for new trays or other applications. We close the loop: our trays are made from recycled materials from day one, both multi-use HerkuPaks and single-use HerkuPaks.” What started as a personal conviction became a marketing asset and has since become a retail requirement.

© Arlette Sijmonsma | MMJDaily.comAlfred Boot at IPM 2026

Internationalization and family businesses
Boot emphasizes the importance of strong chain partners. “We believe in collaboration.” In Europe, the company has always worked with operators from “Portugal to Finland”. Outside of Europe, the company markets directly, which has taken it as far as New Zealand, trips Boot describes as memorable.

North America has also been a rewarding market. There has been significant growth. “With our reusable QuickPot trays and our expertise, we can really add value there.” Is that his favorite market? He is reluctant to pick one. “I enjoyed going there, because we could make a real difference. But the Netherlands remains, perhaps, my first place. Not only because it is our biggest market, but because a lot of it originates here, seeds, ornamental gardens, plant breeding, greenhouse construction. That is the focus of knowledge and quality. Growing with minimal waste, with biological inputs, under constant price pressure. That is not always highly appreciated by the external role. The sector requires a pragmatic mentality, but the achievements are extraordinary. are”.

This has motivated him throughout his career. “This sector is essential. You are either in food or greening the world. Is ornamental horticulture necessary? Yes, I think so.”

That’s why Herkuplast, a family business at heart, chose during the pandemic to do everything in its power to continue serving its customers. After a short stoppage, the factory was opened as soon as possible, adapted to the strict requirements of Germany. “It was a huge peak for horticulture, but the prices of raw materials also rose a lot. We took the risk of buying at high prices and continued to deliver, even though it cost us the margin. But we wanted to continue to supply our customers. The importance of continuity is too great, for our customers, for our people and for our sector.”

After the pandemic, Herkuplast entered an important period of transition. Mr. Kubern had reached his seventieth birthday, and there was no succession in the family. A sale was the expected result, and in 2024 Herkuplast was bought by the Swiss company Bachmann Group. “I’m glad it was Bachmann. Our big priority was to have a private company that understood the European market, understood horticulture and would keep the factory in Germany.” With international expansion and a motivated team launching the new Bachmann-Herku brand, ambitions are high. “And when you look at how the sector is changing, automation, robotization, AI in plant selection, it’s moving at an incredible speed. It’s fascinating.”

© Arlette Sijmonsma | MMJDaily.com And with the new colleagues from Bachmann Herku, IPM 2026

goodbye
But Boot is also honest: from a professional point of view, he won’t be around to see it unfold. The end of March will be his last working day at Herkuplast. “It’s a purely personal choice. I’m not tired of work, and I’m not tired of the sector. But you only live once, and life has a lot to offer.” The caravan is ready. Together with his wife Astrid (known to many in the industry) and their dog, the couple embarks on a long-distance trek. “I’ve been abroad about 100 days a year. We definitely have triplets when the kids were little, so balancing work and family was a constant juggling act. Now we go together.”

He adds: “If I had a long horizon ahead of me at 45, I would love to do again what we did with Herku in 1997. But now I feel too old for that.” He laughs. “And over the years I have become a clone of Herkuplast myself, while the product range has changed with the acquisition. Now we are Bachmann-Herku, and the portfolio is being integrated quickly. Kasper has been working in the new company since his first day. That is also a natural process. It feels good.”

For more information:
Bachmann Herkuplast

Alfred Boot
(email protected)
Kasper Rietveld
(email protected)
+31 653 215 514

Tel.: +41 41 914 72 00
(email protected)
www.bachmann.ch